In China, for many reasons, patients often do not have the awareness to have regular oral examinations and come to the clinic only after the tooth becomes painful. At this time, the condition is often severe and the affected tooth has developed into pulpitis or apical infection, requiring endodontic or root canal treatment. The steps of endodontic treatment are complex and include: nerve inactivation, nerve removal, root canal preparation and disinfection, root canal filling, and filling of the tooth. These treatments cannot be completed in a single visit, and each treatment must be spaced out over a certain period of time, so patients need to be seen several times to complete the treatment.